Voice Silencer on Telephone Lets You Talk in Secret (Feb, 1941)

Voice Silencer on Telephone Lets You Talk in Secret
Your telephone conversation can be made inaudible to others in the same room if the phone is equipped with a new mouthpiece that prevents sound from escaping. It is easily attached to any hand instrument and fits snugly around the speaker’s lips. There is no distortion of the voice. Part of the midget “telephone booth” telescopes to fit the standard cradle phone.